NEW YORK: Sleeping for seven hours a day may reduce the age of your heart as well as decrease the risks for cardiovascular disease, say researchers.

The study showed that excess heart age is the lowest in adults who sleep seven hours a night.

Sleeping times less than or greater than seven hours were associated with increased excess heart age, while short sleepers had the highest elevations in excess heart age.

Sleep duration coupled with excess heart age may prove helpful for communicating the cardiovascular risks and benefits associated with sleep duration.

"These results are important because they demonstrate a quantitative method for the inclusion of sleep duration in the establishment and communication of cardiovascular risk for individuals," said Julia Durmer from the Emory University in Georgia, US.

The study, published in the journal Sleep, included data from 12,775 adults aged between 30-74 years.

They self reported their sleep duration which was classified into five categories -- five hours or less, six, seven, eight, nine and/or more hours of sleep.

The team used sex-specific Framingham heart age algorithm to calculate each individual's heart age and used multivariable linear or logistic regression to examine the association between sleep duration and excess heart age.

The results showed that mean adjusted excess heart age was lowest among adults who reported sleeping seven hours per 24-hour period.

"This could have utility in the clinical care of patients with cardiovascular risk, and for public health researchers interested in adding a sleep metric to future studies," Durmer said.

According to the US-based National Sleep Foundation, people who do not sleep enough are at higher risk for cardiovascular disease and coronary heart disease-regardless of age, weight, smoking and exercise habits.

Sleeping too little causes disruptions in underlying health conditions and biological processes like glucose metabolism, blood pressure and inflammation. However, the same may hold true for over sleeping.